- 期刊
Correlations between C-Scan Ray Tracing Module and Visual Performance in Normal Cornea and Post-LASIK Patients
C掃描光線追蹤模式和視覺表現在正常角膜及LASIK術後病人的相關性
摘要
Objective: C-Scan Ray Tracing is a technique somewhere between conventional corneal topography and true wavefront aberration sensing. The aim of the C-Scan Ray Tracing program is to calculate and represent the imaging characteristics of the cornea, in order to help assess the possible visual acuity. The purpose of this study was to evaluate the correlation between potential corneal visual acuity (PCVA) from the C-Scan, best spectacle-corrected visual acuity (BSCVA), and contrast sensitivity equivalent acuity (CSEA) from the MCT 8000. Patients and Methods: This study included a total of 68 eyes with normal corneas and 120 post-LASIK eyes. BSCVA, MCT8000, and C-Scan were performed in both daytime and nighttime conditions. The correlation was calculated by the Kendall’s correlation coefficient. Results: In normal cornea eyes, PCVA correlated with BSCVA ( p=0.003) and CSEA ( p＜0.001) in daytime conditions, but correlated only with CSEA ( p＜0.001) in nighttime conditions. In post-LASIK eyes, PCVA correlated only with CSEA ( p=0.003) in daytime conditions, and had no significant correlation with BSCVA ( p=0.818) or CSEA ( p=0.141) in nighttime conditions. Conclusions: C-Scan Ray Tracing module has good predictability for visual performance in daytime conditions for normal cornea eyes. However, it has some limitations in predicting precise visual performance of post-LASIK eyes and at nighttime conditions.
並列摘要
Objective: C-Scan Ray Tracing is a technique somewhere between conventional corneal topography and true wavefront aberration sensing. The aim of the C-Scan Ray Tracing program is to calculate and represent the imaging characteristics of the cornea, in order to help assess the possible visual acuity. The purpose of this study was to evaluate the correlation between potential corneal visual acuity (PCVA) from the C-Scan, best spectacle-corrected visual acuity (BSCVA), and contrast sensitivity equivalent acuity (CSEA) from the MCT 8000. Patients and Methods: This study included a total of 68 eyes with normal corneas and 120 post-LASIK eyes. BSCVA, MCT8000, and C-Scan were performed in both daytime and nighttime conditions. The correlation was calculated by the Kendall’s correlation coefficient. Results: In normal cornea eyes, PCVA correlated with BSCVA ( p=0.003) and CSEA ( p＜0.001) in daytime conditions, but correlated only with CSEA ( p＜0.001) in nighttime conditions. In post-LASIK eyes, PCVA correlated only with CSEA ( p=0.003) in daytime conditions, and had no significant correlation with BSCVA ( p=0.818) or CSEA ( p=0.141) in nighttime conditions. Conclusions: C-Scan Ray Tracing module has good predictability for visual performance in daytime conditions for normal cornea eyes. However, it has some limitations in predicting precise visual performance of post-LASIK eyes and at nighttime conditions.